Railway clearance indicator



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Patented Nov. 28, 1933 PATENT OFFICE RAILWAY CLEARANCE INDICATOR MartinW. Clement, Haverford, and Rudolph I Kleine, Philadelphia, and John W.Rowland,

Paoli, Pa.

Application December 20, 1932 Serial ,No. 648,078

16 Claims.

This invention relates to railway clearance indicators, andmoreparticularly to a device for gauging railway cars and their lading todetermine the existence-and location of obstructions "'5 extendingbeyond theminimum clearance diagram of the railroad over which such carsare to be hauled. Clearance diagrams are prescribed by railroads as amatter of safety to insure the safe passage ofcars through tunnels,bridges, It not infrequently happens that cars are too wide or too highfor the clearance limits of the railroad over which the cars are routed;or that lading on cars exceeds the clearance limits; or that portions ofcars such as doors, running boards, roofs, etc.,

1 convenient points, thereby to detect the presence of any obstructionswhich extend beyond safe clearance limits and to identify the locationof such obstructions. To this end our invention comprises a stationarystructure bridging a track and having movable devices pivoted thereonwith their free ends defining a clearance diagram of predeterminedoutline. According to the pre ferred practice of the invention, cars aremoved in groups at a slow uniform speed through the bridging structure,and means are'provided so "that, whenever parts of a car or its ladingproject beyond the clearance diagram, the operator is notified.Additional means are provided to enable the operator to determinereadily the point at 'which the obstruction occurs and to measure theextent to which it exceeds safe clearance limits.

Tne clearance indicator of our invention is especially useful as a partof equipment used for making a comprehensive inspection of railroad carssuch as described in our pending application for U. S. Letters Patent,Serial No. 633,702, filed September 19, 1932. For this purpose theclear- 'ance indicatorpreferably takes the form of a tower. and includesan operators station from which the roofs of passing cars may beobserved for defects, such as loose running boards, ventilators or thelike. Such a clearance tower may be conveniently located between areceiving yard andv a classification yard.

Other objects and advantages characterizing our'invention will becomemore fully apparent from the description hereinafter set forth of oneembodiment or example of the practice thereof,

tabs used for gauging clearance shown in open the indications given tothe operator under the having reference to the accompanying drawings. 9fthe drawings:

Fig. I represents a front elevation of a clearance tower of ourinvention with the swinging position.

Fig. II represents a cross section of the same, taken as indicated bythe lines II-II of Fig. I, with the swinging tabs in closed position.

Fig. III represents an enlarged cross section of a part of the same,taken as indicated by the lines III--III of Fig. I.

Fig. IV represents an enlarged cross section of the same, taken asindicated by the lines IV-=IV of Fig. I, and showingone of the swingingtabs and the manner in whichit is supported.

Fig. V represents an enlarged front elevation of the swinging tab shownin Fig. IV.

Fig. VI represents a cross section of the same, taken as indicated bythe lines VIVI of Fig. V.

Fig. VII represents the indicator panel at the operators stationtogether with a view of the clearance gauge and one of the swinging tabsafter engagement with an obstruction, showing U condition represented.

Fig. VIII represents the indicator panel, clearance gauge and swingingtab while a measurement is being taken.

Fig. IX- represents an enlarged view of a por tion of the face of theindicator panel.

Fig. X represents a cross section of a portion of the indicator panel;and,

Fig. XI represents a perspective view of a portion of a striking plate.I

With reference initially to Figs. I and II,-there is shown in thedrawings a clearance indicator of our invention in the form of a towerbridging a track 41. The tower comprises a framework having upright sidemembers 42 of lattice construction, and a cross member 43 which affordssupport for an operators cabin 44. Ladders 45 are provided at each sideto permit the operator to climb the tower, and a railing 46 extends ateach side of the operators cabin. Access to the operators cabin 44 ishad through a door 47 in the side thereof, and windows 48 are providedat the front and back of the operators cabin to give to the operator alengthwise view of the track in either direction. As shown in Fig. II,the operator is conveniently seated in a swivel chair 49 from which hemay View cars, as they approach or leave the clearance tower.

The framework of the tower includes upright channel beams 50 anddiagonal channel beams 51 to which are hinged vertical and diagonal tabsupports 52a and 52b. Each tab support 52a has ahixed thereto, as shownin Figs. Iv and V, spaced hinge members 53 which are keyed to a verticalshaft 55 at the side of the clearance tower. The vertical shafts 55 arein turn supported for rotation in bearings 56 located at spacedintervals along the channel beams 50 of the side member 42. In likemanner the diagonal tab supports 52b are attached to additional hingemembers 53 which are carried on diagonal shafts 57. The two diagonalshafts 57 at each side of the clearance tower are connected by bevelgearing 58 to a horizontal shaft 59 which is disposed directly beneaththe operators cabin 44. Suspended by hinge members 53 from thehorizontal shaft 59 there is an additional tab support 520. The verticaltab supports 52a have hinged thereto a series of tabs collectivelydesignated at 60a which project inwardly towards the track 41. Likewisethe diagonal tab supports 521) have hinged thereto swinging tabs 60b,and the horizontal tab support 520 has hinged thereto tabs 600 whichproject downwardly towards the track 41. The swinging tabs may take agreat variety of forms, but in the present instance flat wooden paddleshave been selected. 7

It will be observed that the free ends of the three groups of tabs 60a,60b, 60c define a clearance diagram. This diagram is determined by thesafe clearance limits of the railroad for which the clearance tower isdesigned. The diagram may be made to correspond to the outline ofclearances obtained by clearance cars which are in common use byrailroads for ascertaining clearances of objects adjacent to and abovethe tracks.

All of the tabs 60a, 60b, 600 are hinged to their supports 52a, 52b, 520with capacity for independent swinging movement. As illustrated in Figs.IV and V, each tab support 52a comprises a member of wood, or otherinsulating material, having horizontally extending brackets 61 at spacedintervals therealong. To each bracket 61 a tab 60a is hinged by means ofa bolt 62 and wing nut 63 with washers 64 interposed therebetween. Atits hinged end each tab 60a has bolted thereto a U-shaped holder 65 ofconducting material, as shown in Fig. VI, which bears directly againstthe bracket 61. Each tab also carries a strip 66 of conducting material,one end of which is in contact with the tab holder 65 as indicated at67, and the other end of which terminates in a contact member 68 at thefree end of the tab. By adjustment of the wing nuts 63 sufficientfrictional resistance is offered to swingingof the tabs as to cause themto move only under impact with an obstruction.

On different side faces of the tab support 52a there are two conductors69 and '70 which extend throughout the length of the same. The conductor69 is disposed on the side of the tab support 52a upon which thebrackets 61 are mounted and is in electric contact with all of thebrackets 61. The conductor 70 has attached thereto at intervals of itslength clips 72 which are adapted to contact with the lower faces of thetab holders 65 when the tabs are swung away from their normal positions.Thus when a tab 60a is moved from the position shown in full lines inFig. IV to the position shown in broken lines, as soon as the movementis initiated, the holder 65 comes in contact with the clip 72,permitting current to pass from conductor-69 to conductor 70. Theswinging tabs 60b and 600, though somewhat differently shaped, areconstructed in the same manner as the tabs 60a and are hinged to theirrespective tab holders 52b and 52c in the same manner.

Adjacent to each tab holder 52a there is a striking plate 73a comprisinga vertically disposed flat board, as illustrated in Fig. XL having aseries of contact plates 74 located at spaced intervals along the innerface thereof. Adjacent to the diagonal tab holders 52b there are similardiagonal striking plates 73b; and adjacent to the. top or horizontal tabholder 520 there is an additional striking plate 730. All of thestriking plates 73a, 73b, 730 are constructed in the same manner, andhave associated therewith cables 75, as shown in Fig. XI, carrying aseries of individual conductors each one of which is connected to aseparate contact plate 74. The striking plates 73a 73b, 73c are used forthe purpose of returning tabs which have been displaced by the movementof cars through the clearance tower which have obstructions thereonexceeding the limits of the clearance diagram. The striking plates alsoafford a means of completing electrical circuits and thus to giveindications to the man in the operator's cabin of the location of thedisplaced tabs.

For the purpose of enabling the operator to ascertain the location andextent of displacement of a tab struck by a passing car, means areprovided for moving the tabs 60a, 60b, 60c by groups, such means beingcontrolled from the operators cabin by two hand wheels 76 and 77. Thehand wheel '76 is connected through bevel gearing '78 with a shaft 79.The shaft 79 is in'llo turn connected through a Worm gear 80 to thehorizontal shaft 59 which controls movement of the diagonal andhorizontal tab holders 52b and 520. Accordingly, rotation of the handwheel 76 causes simultaneous rotation of the tab holders 52b, 52cwhereby the tabs 60b, 600 may be brought into engagement with thestriking plates 73b, 730. The other hand wheel 77 is connected throughbevel gearing 81 with a shaft 82 which in turn is connected through aworm gear 83 with an additional shaft 84 extending horizontally acrossthe top of the clearance tower. The shaft 84 is connected through bevelgearing 85 with the vertical shafts 55. Accordingly, rotation of thehand wheel 7'7 causes simultaneous rotation '125 of the vertical tabholders 52a, and by such rotation the tabs 60a may be swung intoengagement with the striking plates 73a, thus returning to verticalalignment any tabs which have been displaced by contact with carspassing through'lBO the clearance tower.

In the operators cabin 44 there is provided an indicator panel 86.Thispanel is shown in detail in Fig. IX. It has thereon a series oflights arranged in groups and numbered to correspond! with designatingnumbersion the swinging tabs. In the illustrated example of ourinvention, there are twenty-four tabs in the vertical group at each sideof the tower designated by the numbers 1 to 24. The lights correspondingto these tabs are' collectively designated at a on the indicator panel86. At each side of the clearance tower there are thirteen swinging tabsin the diagonal group 60b, with designating numbers 25-37, the lightscorresponding to which are collectively designated at b, and two moretabs in the horizontal group 600, the lights corresponding to which aredesignated at c. On the indicator panel 86 there are thr e additionallights designated at L, T and R, and designating, respectively, theleft",'150

top 'and right portions of the clearance diagram. The light designatedat L is illuminated whenever 'a tab of the left hand group of tabs aisdisplaced the closing of the circuit being accomplished by contactbetween a tab holder and a clip 72 as explained above. Likewise thelight Tis illuminated whenever any of the tabs 60b, 600 at the'top ofthe clearance diagram are swung out of position; and the light R isilluminated whenever any of the tabs of the right hand group 60a isdisplaced. The conductors 69 and 70 lead from the tab holders 52a, 52b,520, through cables 8'7, to the operators cabin 44 and terminate at theindicator panel 86 behind the lights designated at L, T and R.

The lights of the indicator panel86 in the groups designated'at c, b andc, are illuminated Whenever contact is made between the end of a tab anda striking plate. Assuming, for example, that the hand wheel '77 hasbeen rotated and that the tab designated by the numeral 14 has beendisplaced, it will be apparent that this tab Will be the first to-comein contact with the striking plate 73a. When the tab designated by thenumeral 14' has come in contact with the striking plate 73a, a circuitwill be completed, through one of the conductors of the cable 75, thecontact plate 74 adjacent to the tab, the contact member 68 at the endof the tab, its conducting strip 66, the tab holder 65, and the whereasthe measuring device 89 indicates such measurements relating to thediagonal and horizontal tabs 60b, 600. Each measuring device hasassociated therewith a pointer 90, which is attached to a cable 91, anda counterweight 92 at the end of the cable. As shown clearly in Fig.III, one such cable 91, the one associated with the measuring device 88,is attached to an arm 93 fixed on the horizontal shaft 84 which operatesthe side groups of tabs 60a, whereas the other cable 91 associated withthe measuring device 89 is attached to an arm 94 fixed on the horizontalshaft 59 which operates the diagonal and horizontal groups of tabs 60b,60c.

Sheaves 95 are employed for guiding the cables 91 as they lead downwardfrom the operators cabin and outward and downward to the ends of thearms 93 and 94. The linear movement of each pointer 90 over the face ofthe measuring devices 88, 89 is in direct'proportion to the angularmovement of the shafts 84, 59 and hence in direct proportion .to theangular movement of the tab holders 52a, 52b, 520. By properlypositioning the pointer 90 with respect to the graduated scale on themeasuring device, the apparatus may be arranged so that, when the tabholder 52a is in a plane transverse to the track, the pointer will be atthe base of themeasuring device, as indicated in Fig. VII, whereas whenthe tab holder 52a is at the fully open position shown in broken linesin Fig. VIII, the pointer will be at the top of the measuring device asindicated in the latter figure. With such an arrangement, whenever a tabhas beendisplaced by impact with a passing car and the tab holder isrotated towards the striking plate, a light will appear on the indicatorpanel 86 before the pointer 90 has reached the top of the graduatedscale. The graduations on the measuring devices 88, 89 are thereforemade to correspond with the angular swinging movement of the tabs. Whenan obstruction, such as indicated at O in Figs. I and VII, projectsoutward from a car C to the maximum distance for which the clearancetower is designed, this distance being indicated at the tab engaged bythe obstruction will be displaced and swung to the position shown infull lines in Fig. VII. Subsequent movement of the tab holder 52athrough the angle 11 to the position shown in full lines in Fig. VIII,will bring the tab into contact with the striking plate 73a. At theinstant of contact a light will appear on the indicator panel 86. Atthis point the pointer 90 will have travelled to the position shown inFig. VIII, and the graduation immediately beneath the pointer is ameasurement or" the extent to which the obstruction 0 projects beyondthe clearance diagram.

In Fig. X there is shown a cross section of a portion of the indicatorpanel 86 illustrating the nature of its construction. It comprisesbriefly a base board 96, having thereon a series of terminals 97connected to the contact plates '74 and to the conductors 70, aninsulated plate 98 hav ing sockets 99 for the accommodation of theindicator lights and a hinged glass cover 100.

To afford shelter for the operators station the cabin 44 is preferablyprovided with an overhanging roof 101 to which search lights 102 areconveniently attached, enabling the operator to conduct his work atnight as well as in the day time. The search lights 102 are preferablydi rected lengthwise or" the track.

The operation of the above described clearance tower of our invention isas follows. Cars are moved slowly at a uniform speed through the towerin the direction indicated by the arrow in Fig. VII. The operator in thecabin 44 carefully inspects each car as it approaches the clearancetower and makes a note of all visible defects relating to the roofs orsuperstructures of the cars. Under ordinary conditions, where the carshave no obstructions projecting therefrom beyond the predeterminedclearance diagram, the operators work consists merely of an inspectionof'the upper parts of the cars passing through the tower, and the makingof notes identifying the location of defects so that they can besubsequently remedied. In the event, however, that a car passes throughthe clearance tower having thereon an object projecting beyond theclearance diagram, a light will immediately appear on the indicatorpanel 86 in front of the operator. Assuming that a car such as thatrepresented at C in Fig. I has thereon a projection projecting laterallyaccording to the outline at O in broken lines, it will be apparent thatthe obstruction will cause the tabs having thereon the designatingnumbers 14, 15, 16, to be swung out of the way. Inasmuch as theobstruction has engaged the group of tabs 60a at the right hand side ofthe track, the light R will be illuminated on the instrument 86, the

object on the car passing through the tower, he 50 'proceeds to signalthe train operator to stop the train.

In order to ascertain the location and outline of the obstruction, theoperator then turns the hand wheel '77 to rotate the tab holder 52a. Thehand wheel '77 is turned slowly and as soon as the tab designated by thenumeral 14 engages the striking plate 73a, a light will appear, asrepresented in Fig. VIII, on the group a of lights at the right handside of the indicator panel 86. This light identifies to the operatorthe particular tab at which the maximum obstruction has occurred. Assoon as the light appears, the operator examines the measuring device 88and notes the graduation adjacent to the pointer 90. Having thusascertained the extent of displacement of the tab designated by thenumber 14, the

operator continues to rotate the hand wheel 77 and determines in thesame manner the extent of displacement of tabs numbered 15, 16. When thehand wheel 77 has been rotated to the point where all of the tabs of thegroup have come into engagement with the striking plate 73a, it will beapparent that the displaced tabs will be returned to a common verticalplane. With the tabs thus re-aligned, operator moves the hand wheel 77in the opposite direction, returning the tabs of the group. to a planetransverse to the track 41.

Having noted the location and outline of the obstruction, the operatorthen signals the train to proceed. From the operators notes the carhaving thereon the obstruction is identified and corrective actiontaken.

From the above description it will be apparent that the clearance towerof our invention affords a safeguard against accidents occurring byreason of projecting objects on railway cars which exceed the clearancelimits of the right-ofway over which the cars pass,

While the invention has been described with reference to a preferredembodiment in which a clearance tower forms a part of a comprehensiveinspection of railway cars, it will be apparent that the principle ofour invention may be utilized to advantage for the sole purpose ofgauging cars for objects exceeding clearance limits, and it will befurther apparent that the particular forms of the various devicesspecifically.

referred to herein admit of considerable change and re-arrangementwithout departure from the spirit of our invention as defined in theannexed claims.

Having thus described our claim:

1.. A rair y clearance indicator comprising a framework bridging atrack, a series of tabs projecting inwardly from said framework withtheir ends defining a diagram, means for mounting said tabs on saidframework withv capacity for independent movement away from said track,and for indicating the location of tabs displaced by contact withobjects passing through said framework and projecting beyond saidclearance diagram.

2. A railway clearance indicator comprising a framework bridging atrack, a series of tabs projecting inwardly from said framework withtheir ends defining a clearancediagram, means for mounting said tabs onsaid framework with capacity for independent movement away from saidtrack, means for indicating the location of tabs displaced by contactwith objects passing through invention, we

said framework and projecting beyond said diagram, and means formeasuring the extent of displacement of such tabs.

3. A railway clearance indicator comprising a, framework bridging atrack, a series of tabs normally projecting inwardly from said frameworkin a common vertical plane with their ends defining a clearance diagram,means for mounting said tabs on said framework with capacity forindependent swinging movement away from said track, and mechanical meansfor moving said tabs by groups. whereby, when one or more tabs have beendisplaced, all the tabs of a group may be returned to the commonvertical plane.

4. A railway clearance indicator comprising a framework bridging atrack, a series of tabs normally projecting inwardly from said frameworkin a common vertical plane with their ends defining a clearance diagram,means for mounting said tabs onsaid framework with capacity forindependent swinging movement away from said track, a striking plate onsaid framework adjacent to said tabs, and means for swinging said tabsto contact with said striking plate, whereby, when one or more tabs havebeen displaced, all the tabs may be returned to the common verticalplane. 7

5. A railway clearance indicator comprising a framework bridging atrack, a group of tabs projecting downwardly from the top of saidframework towards the track, additional groups of tabs projectinginwardly from each side of said framework towards the track, means formounting said tabs on said framework with capacity for independentswinging movement, and means for indicating the particular group whereintabs have been displaced by contact with cars passing through saidframework.

6. A railway clearance indicator comprising a framework bridging atrack, a group of tabs projecting downwardly from the top of saidframework towards the track, additional groups of tabs projectinginwardly from each side of said framework towards the track, means formounting said tabs on said framework with capacity for'independentswinging movement, means for indicating the particular group whereintabs have been displaced by contact with cars passing through saidframework, and means for indicating the particular tabs of such groupwhich have been displaced.

'7. A railway clearance indicator comprising a. framework bridging atrack, a group of tabs projecting downwardly from the top of saidframework towards the track, additional groups .of tabs projectinginwardly from each side of the framework towards the track, said tabsbeing normally disposed in a common vertical plane, means for mountingsaid tabs on said framework with capacity for independent swingingmovement, striking plates on said framework adjacent said groups oftabs, and means for swinging all the tabs of a group together to contactwith a striking plate, whereby, when one or more tabs of a group havebeen displaced, all tabs of the group may be returned to the commonplane.

8. A railway clearance indicator comprising a framework bridging atrack, a tab support, means for pivotally mounting said tab support onframework, a series of tabs. means for mounting said tabs on saidsupport with capacity for independent swinging movement thereon, saidtabs normally projecting inwar ly from the framework in a commonplane-with their ends defining a clearance diagram, a striking plate onsaid framework, and means for moving the tab support to effectengagement between the tabs thereon and the striking plate, whereby,when one or more tabs have been displaced, all of the tabs may bereturned to the common plane.

9. A railway clearance indicator comprising a framework bridging atrack, a tab support, means for pivotally mounting said tab support onsaid framework, a series of tabs, means for mounting said tabs on saidsupport with capacity for independent swinging movement thereon,saidtabs projecting inwardly from the framework with their free endsdefining a clearance diagram, a striking plate on said framework, meansfor moving the tab supports to effect engagement between the tabsthereon and the striking plate, and means for measuring the angularmovement of the tab support whenever a tab engages the striking plate.

10. A railway clearance indicator comprising a framework bridging atrack, a tab support, means for pivotally mounting said tab support onsaid framework, a series of tabs, means for mounting said tabs on saidsupport with capacity for independent swinging movement thereon, saidtabs projecting inwardly from the framework with their free endsdefining a clearance diagram, a striking plate on said framework, meansfor moving the tab supports to effect engagement between the tabsthereon and the striking plate, means for indicating the instant ofcontact, whenever a tab engages the striking plate, and the location ofsuch tab, and means for measuring the angular movement of the tabsupport, whereby, when a tab engages the striking plate, the extent ofits displacement may be determined.

11. A railway clearance tower comprising a framework bridging a track,said framework including an operators station from which cars passingalong the track may be viewed, a series of independently movable tabsprojecting from said framework towards the track, the free ends of saidtabs defining a clearance diagram; means for indicating at the operatorsstation the location of tabs displaced by contact with cars passingthrough said framework, and means for indicating at said operatorsstation the extent of displacement of such tabs.

12. A railway clearance tower comprising a framework bridging a track,said framework including an operators station from which cars passingalong the track may be viewed, a series of independently movable tabsprojecting from said framework towards the track and normally disposedin a common vertical plane, said tabs being arranged in groups at thesides and above said track, and means operable from said operatorsstation for moving said tabs by groups, whereby, when one or more tabshave been displaced by cars passing through said framework, all the tabsof a group may be returned to the common vertical plane.

13. A railway clearance tower comprising a framework bridging a track,said framework including an operators station commanding a Viewlengthwise of the track, a series of tabs projecting inwardly from saidframework normally in a common vertical plane, means for mounting saidtabs on said framework with capacity for independent swinging movementthereon, a striking plate on said framework adjacent to said tabs, andmeans operable from said operators station for swinging said tabs tocontact with said striking plate, whereby, when one or more tabs havebeen displaced by cars moving through said framework, all the tabs maybe returned to the common vertical plane.

14. A railway clearance tower comprising a framework bridging a track,said framework including an operators station above the track, tabsprojecting downwardly from the top of said framework towards the track,and inwardly from each side of said framework towards the track, saidtabs being independently movable on said framework and normallyoccupying a position transverse to the track, means for indicating atsaid operators station the tabs displaced by cars passing through saidframework, and means controlled at said operators station for returningdisplaced tabs to their normal position.

15. A railway clearance tower comprising a framework bridging a track,said framework including an operators station above the track, a groupof tabs projecting downwardly from the top of said framework towards thetrack, an additional group of tabs projecting inwardly from each side ofsaid framework towards the track, said tabs being independently movableon said framework, and means for indicating at said operators stationthe particular group wherein tabs have been displaced by contact withcars passing through said framework, and means for indicating at saidoperators station the tabs of such group which have been displaced.

16. A railway clearance tower comprising a framework bridging a track,said framework including an operators station, a series of independentlymovable tabs projecting inwardly from said framework and normallyaligned in a vertical plane with their free ends defining a clearancediagram, means responsive to the displacement of a tab, inciden to thepassage of a car exceeding the clearance limits of said diagram throughsaid framework, for producing a signal at said operators station, meanscontrolled from said operators station for rotating said tabscollectively thereby to re-align displaced tabs, and means responsive tosuch collective rotation of the tabs for indicating said operatorsstation the location of the tabs which have been displaced.

MARTIN W. CLEMENT. RUDOLPH L. KLEINE. JOHN W. ROWLAND.

